The invention relates generally to the use of micro fiber-optic technology to inspect a beam surface. More specifically, the invention relates to inspecting a concealed surface of a beam by inserting a micro fiber-optic thread of a micro fiber-optic borescope between the beam and a structure concealing the surface.
Inspection of a beam, such as a floor beam of an aircraft, for corrosion and/or cracks, usually requires the removal of whatever structure is mounted on the beam, for example floor panels. If a complex structure, such as an aircraft lavatory, is mounted to the beam, removal of such a structure in order to inspect the concealed surface of the beam is difficult, labor intensive, and very costly.
For example, maintenance programs for a commercial airline aircraft typically require heavy maintenance checks to be performed between every 5 to 7 years. During heavy maintenance checks, the floor structure is inspected for corrosion damage by completely removing everything that is mounted to the floor beams, including floor panels and all structures above the floor panels. Corrosion damage to the aluminum floor beams of an aircraft most frequently happens around xe2x80x98wetxe2x80x99 areas, near entry doors and under lavatories and galleys, which can leak fluids. Such corrosion damage is most frequently found on the upper surface of the aluminum floor beam, and particularly around the fastener holes used to attach the floor panels to the floor beams.
In order to inspect the upper surface of the floor beam, the airline inspection crew must remove the lavatories, seats, galleys, closets, etc., and then remove the floor panels. On the average, removing one galley, taking up the floor panels, inspecting the beams, replacing beams or treating the beams with a corrosion inhibiting compound, and then replacing the floor and galley, can require over 600 hours of labor per galley (or lavatory, etc.), thereby making such an inspection/repair process very costly.
Therefore, it would be highly desirable to be able to inspect a concealed surface of a beam, such as an aircraft floor beam, without having to remove the structure mounted to the beam.
In one preferred embodiment, the present invention is directed to a system for inspecting a surface of a beam covered by at least one structure. The system includes at least one nut clip attached to the beam used to couple the structure to the beam and create a gap between the structure and the beam. Additionally, the system includes a micro fiber-optic borescope used to view the surface of the beam covered by the structure without removing the structure. Alternatively, the system also includes at least one spacer inserted between the beam and the structure for creating the gap between the structure and the beam. The surface is viewed by inserting a micro fiber-optic thread of the borescope into the gap.
The present invention also involves a method for inspecting a surface of a beam covered by at least one structure. The method includes attaching the structure to the beam utilizing a nut clip having an upper leg and a lower leg, wherein the upper leg is shorter than the lower leg. The method also includes creating a gap between the beam and the structure utilizing the upper leg of the nut clip, and viewing the beam surface covered by the structure utilizing a micro fiber-optic borescope. Alternatively, the method includes inserting at least one spacer between the beam and the structure, thereby creating the gap between the beam and the structure.
In another preferred embodiment an apparatus is provided for securing panels over an upper surface of a support beam to permit inspection of the beam upper surface. The apparatus includes a plurality of nut clips attached to the beam for mounting the panels to the beam, and at least one spacer inserted between the beam upper surface and the panel. The spacer creates a gap between the beam upper surface and the panel. The gap is sufficient to introduce a micro fiber-optic thread of a micro fiber-optic borescope used to view the covered surface of the beam.